Method for embedding integrated circuit flip chip

ABSTRACT

Embodiments of the invention relate to processes for fabricating a smart device (200), e.g. smart card, and configurations for smart card devices with greater reliability and lifespan, and improved finish. In the smart card device comprising of laminated substrate layers (220, 240) interposing a flexible film (230) having conductor pattern thereon, at least one flip chip (250) for operating the smart card device is embedded in a first substrate (220) such that the first substrate provides an encapsulation to the at least one flip chip, wherein the at least one flip chip (250) is arranged at a position in a first vertical plane; and a contact pad (260), for providing electrical connection when the smart card device is inserted into a smart card reader, is arranged at a position in a second vertical plane, wherein the first vertical plane is non-overlapping with the second vertical plane. The contact pad (260) is projected through a cavity in a second substrate to form a continuous even plane from an outer surface of the laminated substrate layers to the contact pad (260).

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is the U.S. national phase under 35 U.S.C. 371of international patent application number PCT/SG2016/050574 filed onNov. 22, 2016, which designated the U.S., and which claimed priority toU.S. provisional patent application No. 62/263,105 filed on Dec. 4,2015, which are incorporated herein by reference.

FIELD OF INVENTION

The invention relates to manufacture of smart card devices with improvedlifespan, reliability and aesthetics, and methods of manufacturing thatreduce production steps and costs.

BACKGROUND

An integrated circuit (IC) module, of smart-type, that can be either asecure microcontroller or equivalent intelligence with internal memoryor a memory chip alone, is normally packaged or embedded in a carrier(e.g. card). The resulting smart card device can be capable ofconnecting to a reader by direct physical contact, i.e. usingcontact-type interface defined by ISO (International Organization forStandardization) 7816, or by a remote contactless radio frequencyinterface, i.e. using contactless-type defined by ISO 14443, or both,i.e. using dual interface. With the embedded microcontroller, smart carddevices are capable of storing large amounts of data, performing on-cardfunctions (e.g. encryption, mutual authentication) and interactingintelligently with a smart card reader for various applications (e.g.banking, payment, telecommunications). The smart card devices may bepackaged into various form factors (e.g. plastic cards, key fobs,watches, subscriber identification modules used in GSM mobile phones,USB-based tokens, the Secure Digital (SD), mini/micro SD, MMC, VQFN8,SSOP20, TSSOP20, MemorySticks cards, etc).

Generally, a method for fabricating a dual interface smart card deviceincludes:

-   -   1(a) assembling IC chips with wire bonding connections and        encapsulation onto a flexible substrate with metallic contact        pads, wherein at least one IC chip and two antenna contact pads        are mounted on the underside of a metallic contact pad to        produce an IC module (FIG. 1A shows multiple IC modules 110,        having contact pad layouts according to ISO 7816, being        assembled on a flexible substrate);    -   1(b) laminating a few substrate layers, which comprise an        antenna coil inlay 130 interposed between two substrates 120,        140 of equal thickness, to produce a carrier core;    -   1(c) milling the laminated carrier core to provide a plurality        of first cavities wherein each first cavity is to receive an IC        module;    -   1(d) at each first cavity, further milling the laminating        carrier a plurality of second cavities, which are smaller than        the first cavity, to expose parts of the antenna wire coil;    -   1(e) joining the exposed parts of the antenna wire coil to the        two antenna contact pads provided on the underside of the        contact pad;    -   1(f) disposing an IC module into each first cavity such that a        hot-melt tape on the underside of the IC module is applied to        the laminated carrier core;    -   1(g) applying heat and pressure to the IC module to embed the IC        module in the laminated carrier core.

In step 1(e) above, the antenna coil may be joined to the antennacontacts on the underside of the IC module by using traditional wiresoldering, flexible bumps or insertion of conductive materials to solderonto the antenna contacts to form an electrical connection from the ICmodule to the antenna coil to allow performance of contact-type andcontactless-type transactions.

Generally, a method for fabricating a single interface, i.e.contact-type, smart card device includes:

-   -   2(a) assembling IC chips with wire bonding connections and        encapsulation onto a flexible substrate with metallic contact        pads, wherein at least one IC chip and two antenna contact pads        are mounted on the underside of a metallic contact pad to        produce an IC module (FIG. 1A shows multiple IC modules, having        contact pad layouts according to ISO 7816, being assembled on a        flexible substrate);    -   2(b) laminating a few substrate layers, which comprise two        substrates of equal thickness, to produce a laminated carrier        core;    -   2(c) milling the laminated carrier core to provide a plurality        of first cavities wherein each first cavity is to receive an IC        module;    -   2(d) disposing an IC module into each first cavity such that a        hot-melt tape on the underside of the IC module is applied to        the laminated carrier core;    -   2(e) applying heat and pressure to the IC module to embed the IC        module in the laminated carrier core.

FIG. 1B shows a cross-sectional view of a smart card device 100 having awire-bonded encapsulated IC module 110 embedded in a laminatedarrangement. In the IC module 110, the IC chip 150 is provided withencapsulation 152 and located directly underside of the contact pad 160.

SUMMARY

According to a first aspect of the invention, a method for fabricating asmart card device is provided. The method comprises:

-   -   providing a carrier core in which a flexible film having a        plurality of conductor patterns is interposed between a first        substrate and a second substrate, wherein each of the conductor        patterns includes:    -   at least one flip chip arranged at a position in a first        vertical plane,    -   at least one contact pad arranged at a position in a second        vertical plane,    -   at least one conductor path electrically coupling the at least        one contact pad to the at least one flip chip, wherein the first        vertical plane is non-overlapping with the second vertical        plane, wherein the step of providing a carrier core in which a        flexible film having a plurality of conductor patterns is        interposed between a first substrate and a second substrate        further includes: exposing the at least one contact pad through        at least one cavity in the second substrate; and    -   laminating the carrier core to produce a laminated carrier core        in which the at least one contact pad is projected through the        at least one cavity in the second substrate to form a continuous        even plane from an outer surface of the laminated carrier core        to the at least one contact pad.

In one embodiment of the first aspect of the invention, the step ofproviding a carrier core in which a flexible film having a plurality ofconductor patterns is interposed between a first substrate and a secondsubstrate further includes:

-   -   overlaying the flexible film on the first substrate to produce a        temporary core;    -   laminating the temporary core to produce a laminated temporary        core; and    -   overlaying a second substrate on the laminated temporary core to        produce the carrier core.

In one embodiment of the first aspect of the invention, the step ofproviding a carrier core in which a flexible film having a plurality ofconductor patterns is interposed between a first substrate and a secondsubstrate further includes:

-   -   abutting the at least one flip chip to the first substrate, and        the step of laminating the carrier core to produce a laminated        carrier core further includes:    -   embedding the at least one flip chip into the first substrate.

In one embodiment of the first aspect of the invention, the firstsubstrate is devoid of cavity.

In one embodiment of the first aspect of the invention, the firstsubstrate is provided with at least one cavity having at least onedimensional measurement no greater than at least one dimensionalmeasurement of the at least one flip chip, and wherein the at least onecavity of the first substrate is dimensioned to at least partiallyreceive the at least one flip chip therein. The at least one dimensionalmeasurement is selected from the group consisting of height, length andwidth.

In one embodiment of the first aspect of the invention, the step ofproviding a carrier core in which a flexible film having a plurality ofconductor patterns is interposed between a first substrate and a secondsubstrate further includes:

-   -   abutting the at least one flip chip to the second substrate, and        the step of laminating the carrier core to produce a laminated        core further includes:    -   embedding the at least one flip chip into the second substrate.

In one embodiment of the first aspect of the invention, the step oflaminating the carrier core to produce a laminated core furtherincludes:

-   -   subjecting the carrier core to a hot cycle, wherein subjecting        the carrier core to a hot cycle includes subjecting the carrier        core to high temperature of at least 80° C. and applying        pressure of at least 20×10⁵ pascal (Pa) to the carrier core; and    -   subjecting the carrier core to a cold cycle, wherein subjecting        the carrier core to a cold cycle includes subjecting the core to        low temperature of no more than 30° C. and applying pressure of        at least 20×10⁵ pascal (Pa) to the carrier core.

In one embodiment of the first aspect of the invention, the methodfurther comprises: cutting the laminated carrier core into a pluralityof individual sections.

In one embodiment of the first aspect of the invention, the step ofcutting the laminated carrier core into a plurality of individualsections further includes:

-   -   cutting each of the individual sections as ID-1 size according        to ISO 7810, wherein each of the individual sections includes at        most one of the at least one conductor pattern.

In one embodiment of the first aspect of the invention, the at least onecontact pad is dimensioned according to ISO 7816.

In one embodiment of the first aspect of the invention, the first andthe second vertical plane are non-overlapping with a third verticalplane, wherein an embossing area, which is designated on each of theindividual section according to ISO 7811, is arranged at a position inthe third vertical plane.

In one embodiment of the first aspect of the invention, a thickness ofthe first substrate is greater than a thickness of the second substrate.

In one embodiment of the first aspect of the invention, each of theconductor patterns further includes at least one antenna coil arrangedon the flexible film and at a position in a fourth vertical plane, andwherein the fourth vertical plane is non-overlapping with the first andthe second vertical plane, and wherein the at least one antenna coil iselectrically coupled to the at least one flip chip.

According to a second aspect of the invention, a smart card device isprovided. The smart card device comprises:

-   -   a laminated carrier core comprising:        -   a first substrate;        -   a second substrate; and        -   a flexible film having a conductor pattern and interposed            between the first and the second substrate, wherein the            conductor pattern includes:        -   at least one flip chip embedded into the first or the second            substrate, wherein the at least one flip chip is arranged at            a position in a first vertical plane,        -   a contact pad arranged at a position in a second vertical            plane,        -   at least one conductor path electrically coupling the            contact pad to the at least one flip chip, wherein the first            vertical plane is non-overlapping with the second vertical            plane, and wherein the contact pad is projected through a            cavity in the second substrate to form a continuous even            plane from an outer surface of the laminated carrier core to            the contact pad.

In one embodiment of the second aspect of the invention, the laminatedcarrier core is dimensioned as ID-1 size according to ISO 7810.

In one embodiment of the second aspect of the invention, the contact padis dimensioned according to ISO 7816.

In one embodiment of the second aspect of the invention, an embossingarea, which is designated on the laminated carrier core according to ISO7811, is arranged in a position in a third vertical plane, wherein thethird vertical plane is non-overlapping with the first and the secondvertical plane.

In one embodiment of the second aspect of the invention, the embossingarea is configured to be embossed with information being at least oneselected from the group consisting of identification number, name andaddress.

In one embodiment of the second aspect of the invention, the at leastone flip chip and the contact pad are arranged on opposite sides of theflexible film.

In one embodiment of the second aspect of the invention, the at leastone flip chip and the contact pad are arranged on same side of theflexible film.

In one embodiment of the second aspect of the invention, the conductorpattern further includes at least one antenna coil electrically coupledto the at least one flip chip, wherein the at least one antenna coil isprovided at a position in a fourth vertical plane, and wherein thefourth vertical plane is non-overlapping with the first and the secondvertical plane.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be described in detail with reference to theaccompanying drawings, in which:

FIG. 1A shows an assembly of IC modules to be used in an existing methodfor fabrication of smart card device;

FIG. 1B shows a cross-sectional view of a prior art smart card device;

FIGS. 2A to 2C show a first substrate, a flexible film and a secondsubstrate, respectively, according one embodiment of the invention;

FIG. 2D shows overlaying the flexible film of FIG. 2B on the firstsubstrate of FIG. 2A to produce a temporary core;

FIG. 2E shows overlaying of the second substrate of FIG. 2C on alaminated temporary core to produce a carrier core;

FIG. 2F shows a laminated carrier core prior to cutting into individualsections;

FIG. 2G shows a cross-sectional view of a smart card device which isobtained from a cut section of the laminated carrier core of FIG. 2F;

FIG. 2H is a partial close-up view of the flexible film of FIG. 2B andshows one conductor pattern in which a contact pad and conductor pathsare arranged on a top surface of the film and a flip chip is arranged ata bottom surface of the film;

FIG. 2I shows another example of a flexible film having one conductorpattern in which a contact pad and conductor paths are arranged on a topsurface of the film while a flip chip module is arranged at a bottomsurface of the film;

FIG. 2J shows one example of a contact pad;

FIGS. 3A to 3C show a first substrate, a flexible film with antennacoils and a second substrate, respectively, according one embodiment ofthe invention;

FIG. 3D shows overlaying the flexible film of FIG. 3B on the firstsubstrate of FIG. 3A to produce a temporary core;

FIG. 3E shows overlaying of the second substrate of FIG. 3A a laminatedtemporary core to produce a carrier core;

FIG. 3F shows a laminated carrier core prior to cutting into individualsections;

FIG. 3G shows a cross-sectional view of a smart card device which isobtained from a cut section of the laminated carrier core of FIG. 3F;

FIG. 3H is a partial close-up view of the flexible film of FIG. 3B andshows one conductor pattern in which a contact pad, conductor paths andantenna coil are arranged on a top surface of the film, while a flipchip is arranged at a bottom surface of the film;

FIG. 3I shows another example of a flexible film having one conductorpattern in which a contact pad, conductor paths and an antenna coil arearranged on a top surface of the film, while a flip chip is arranged ata bottom surface of the film;

FIG. 4 shows a flow chart for a method for fabricating a smart deviceaccording to one embodiment of the invention;

FIG. 5 shows a flow chart for a method for fabricating a smart carddevice according to one embodiment of the invention; and

FIG. 6 shows a cross-sectional view of a smart card device in which theflip chip and the contact pad are arranged on the same side of theflexible film.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of various illustrativeembodiments of the invention. It will be understood, however, to oneskilled in the art, that embodiments of the invention may be practicedwithout some or all of these specific details. It is understood that theterminology used herein is for the purpose of describing particularembodiments only, and is not intended to limit the scope of theinvention. In the drawings, like reference numerals refer to same orsimilar functionalities or features throughout the several views.

It should be understood that the terms “comprising,” “including,” and“having” are intended to be open-ended and mean that there may beadditional elements other than the listed elements. Use of identifierssuch as first, second, third and fourth should not be construed in amanner imposing any relative position or time sequence betweenlimitations. Furthermore, terms such as “top”, “bottom”, “side”,“under”, “vertical” used herein are merely for ease of description andrefer to the orientation of the components as shown in the figures. Itshould be understood that any orientation of the components describedherein is within the scope of the invention.

Reference is made to FIGS. 2A to 2J and FIG. 4. According to oneembodiment of the invention, a method for fabricating a smart carddevice 200 of contact type interface includes the following steps:

In block 401, a flexible film 230 or sheet inlay, having at least oneconductor or circuit pattern 210, is provided. FIG. 2B is a schematicrepresentation of a flexible film 230 or sheet inlay having multipleconductor patterns 210.

The flexible film 230 is non-metallic and may be made of plastic, e.g.polyethylene terephthalate (PET). The flexible film 230 may betransparent.

Each conductor or circuit pattern 210 includes at least one flip chip250 arranged on (e.g. bonded to) a bottom surface of the flexible film230 and disposed at a position in a first vertical plane.

Each conductor pattern 210 further includes a metallic contact pad 260arranged on a top surface of the flexible film 230 and disposed at aposition in a 30 second vertical plane. The second vertical plane isnon-overlapping with the first vertical plane. Accordingly, the flipchip is not disposed directly under the contact pad 260. Each contactpad 260 provides electrical conductivity when the smart card device isinserted into a smart card reader, e.g. computer, point of saleterminal. Physical and electrical characteristics of the contact pad 260may be defined according to ISO 7816, in particular ISO 7816-2.

Each conductor pattern 210 further includes conductor paths 270 providedon the top and/or the bottom surface of the film 230 to provideelectrical connection to and from the flip chip 250, contact pad 260,and/or any other components. The conductor paths 270 include at leastone conductor path traversing a thickness of the flexible film 230 toelectrically couple the contact pad 260 to the flip chip 250. Suchconductor path may be embedded in the flexible film 230 by techniquessuch as but not limited to piercing through hole or mechanical rivetingtechniques to provide electrical coupling between the contact pad 260and the flip chip 250.

FIG. 2H is a partial close-up view of the flexible film of FIG. 2Bwherein the contact pad 260 and certain conductor paths 270 are arrangedon a top surface of the film 230 while a flip chip 250 is arranged on abottom surface of the film 230.

FIG. 2I shows one example of a conductor pattern 210 provided on aflexible film 230 wherein the contact pad 260 and certain conductorpaths 270 are arranged on a top surface of the film 230 while a flipchip 250 is arranged on a bottom surface of the film 230.

It is to be appreciated that the contact pads and conductor paths areformed or built on the flexible film 230 by known methods, e.g. dryetching.

In block 403, the flexible film 230 is overlaid or stacked on a firstsubstrate 220 to produce a temporary core 225 a. This step includesapplying an adhesive to one or both of the first substrate 220 andflexible film 230, and abutting the bottom surface of the flexible film230 and the at least one flip chip 250 to the first substrate 220 (seeFIG. 2D).

In one embodiment, the first substrate 220 (see FIG. 2A) is providedwith at least one cavity 222 which is arranged to align with and atleast partially receive the at least one flip chip when the flexiblefilm 230 is laid or stacked upon the first substrate 220. The cavity 222has at least one dimensional measurement which is no greater than atleast one dimensional measurement of the at least one flip chip 250 suchthat the at least one cavity 222 of the first substrate 220 isdimensioned to at least partially receive the at least one flip chip 250therein. The at least one dimensional measurement is selected from thegroup consisting of height, length and width of the respective cavity222 or flip chip 250.

In another embodiment, the first substrate 220 (not shown) is devoid ofcavity.

In block 405, the temporary core 225 a is subject to a first laminationcycle to produce a laminated temporary core 225 b in which the at leastone flip chip 250 is embedded into and encapsulated by the firstsubstrate 220.

Particularly, the temporary core 225 a is placed or interposed betweenlaminator plates. This arrangement comprising of laminator platestogether with the interposed temporary core 225 a is fed into alamination machine where the temporary core 225 a is subject to a firsthot cycle for a period of time, e.g. about 30 minutes. The first hotcycle includes subjecting the temporary core 225 a to high temperature,e.g. at least 80° C., and applying pressure, e.g. at least 20 bars or20×10⁵ pascal (Pa), to the temporary core 225 a. Subsequently, thetemporary core 225 a is subject to a first cold cycle for a period oftime, e.g. about 20 minutes. The first cold cycle includes subjectingthe temporary core 225 a to low temperature, e.g. no more than 30° C.and applying pressure, e.g. at least 20 bars or 20×10⁵ pascal (Pa), tothe temporary core 225 a. It is to be appreciated that the timeduration, temperature conditions, and pressure conditions may bemodified, as known to persons skilled in the art, according to materialsand equipment being used.

Due to pressure and temperature conditions during the first hot cycle,the first substrate 220 is softened and the flip chip(s) 250 are pressedor embedded into the softened first substrate 220. During the first coldcycle, the temporary core 225 a is cooled and hardened. After completingthe first cold cycle, a laminated temporary core 225 b is produced inwhich the at least one flip chip 250 is embedded in the first substrate220 such that the first substrate 220 provides an encapsulation to theat least one flip chip 250.

In block 407, a second substrate 240 is overlaid or stacked on thelaminated temporary core 225 b to produce a carrier core 225 c. Thisstep includes applying an adhesive to one or both of the secondsubstrate 240 and flexible film 230, abutting the top surface of thefilm 230 to the second substrate 240 and exposing the at least onecontact pad 260 through at least one cavity 242 in the second substrate240. The second substrate 240 (see FIG. 2C) is provided with at leastone cavity 242 which is dimensioned to at least accommodate the contactpad 260 therein.

In one embodiment, a thickness of the first substrate 220 is greaterthan a thickness of the second substrate 240.

In another embodiment, a thickness of the first substrate 220 issubstantially the same as a thickness of the second substrate 240.

In block 409, the carrier core 225 c is subject to a second laminationcycle to produce a laminated carrier core 225 d (see FIG. 2F) in whichthe at least one contact pad 260 is projected through the at least onecavity 242 in the second substrate 240 to form a continuous even planefrom an outer surface of the laminated carrier core 225 d to the atleast one contact pad 260.

Particularly, the carrier core 225 c is placed or interposed betweenlaminator plates. This arrangement comprising of laminator platestogether with the interposed carrier core 225 c is fed into a laminationmachine where the carrier core 225 c is subject to a second hot cyclefor a period of time, e.g. about 30 minutes. The second hot cycleincludes subjecting the carrier core 225 c to high temperature, e.g. atleast 80° C., and applying pressure, e.g. at least 20 bars or 20×10⁵pascal (Pa), to the carrier core 225 c. Subsequently, the carrier core225 c is subject to a second cold cycle for a period of time, e.g. about20 minutes. The second cold cycle includes subjecting the carrier core225 c to low temperature, e.g. no more than 30° C., and applyingpressure e.g. at least 20 bars or 20×10⁵ pascal (Pa), to the carriercore 225 c. During the second cold cycle, the carrier core 225 c iscooled and hardened. After completing the second cold cycle, a laminatedcarrier core 225 d is produced. It is to be appreciated that the timeduration, temperature conditions, and pressure conditions may bemodified, as known to persons skilled in the art, according to materialsand equipment being used.

Due to pressure and temperature conditions during the second hot cycleand the presence of each cavity 242 accommodating each contact pad 260,each contact pad 260 and, in some embodiments, a portion of the flexiblefilm 230 surrounding the contact pad 260 are urged into and through thespace of the cavity 242. Further projection of the contact pad 260 andany surrounding portion of the film 230 through the cavity 242 areconstrained by the laminator plates and, accordingly, in the laminatedcarrier core 225 d, a continuous even plane from an outer surface of thelaminated carrier core 225 d to the at least one contact pad 260 isachieved. In other words, no groove or gap will be observed in the areaaround contact pad 260. The result is an aesthetically pleasing andcontinuously even surface on the side of the laminated carrier core 225d where the contact pad 260 is visible and located.

In block 411, the laminated carrier core 225 d is cut or diced intoindividual sections. A schematic representation of the dimensions of anindividual section 200 is illustrated in FIG. 2F.

In one embodiment, each individual section 200 is dimensioned for creditcard or bank card applications, e.g. ID-1 size according to ISO 7810,and at least includes the least one flip chip 250, contact pad 260 andconductor paths. Accordingly, each section is capable of being providedas a smart card device. It is to be appreciated that each section maytake on other dimensions for other applications, e.g. USB token.

In the above-described method, the first and the second vertical planeare non-overlapping with a third vertical plane wherein an embossingarea, which is designated on the ID-1 size laminated carrier coreaccording to ISO 7811, particularly ISO 7811-3, is arranged at aposition in the third vertical plane.

It is to be appreciated that although the foregoing paragraphs and FIGS.2B, 2D, 2G, 2H, 2I, 3B, 3D, 3F, 3H, 3I describe a conductor pattern 210in which the flip chip 250 and the contact pad 260 are arranged onopposite sides of the flexible film 230, it is to be appreciated thatcertain other embodiments can employ conductor patterns in which theflip chip and the contact pad are arranged on the same side of theflexible film, e.g. on the top surface of the film.

According to one embodiment of the invention, a method for fabricating asmart card device 200 of dual interface type, i.e. contact andcontactless interfaces, is provided as described according to blocks 401to 411 with appropriate modifications including but not limited to thefollowing. For example, in block 401, at least one antenna coil 280 isprovided or formed, e.g. by dry etching, on the top surface or thebottom surface of the film 230 and at a position in a fourth verticalplane, and wherein the fourth vertical plane is non-overlapping with thefirst and the second vertical plane, and wherein the at least oneantenna coil 280 is electrically coupled to the at least one flip chip250 by one or more conductor paths 270. Further, each conductor patternmay include two flip chips for respectively operating the contact andcontactless interfaces of the smart card device. It is to be appreciatedthat the antenna coil may take the dimensions of slightly smaller thanID-1 size, half ID-1 size, quarter ID-1 size or other suitabledimensions.

Reference is made to FIG. 5 illustrating a method for fabricating asmart card device 200 of contact type interface or dual interface (e.g.contact and contactless interfaces) according to one embodiment of theinvention. As the features and characteristics of flexible film,conductor pattern, first substrate and second substrate would be similarto the foregoing description in relation to FIG. 4, their details willnot be reproduced here.

In block 501, a carrier core is provided, in which a flexible filmhaving a plurality of conductor patterns is interposed between a firstsubstrate and a second substrate. This step includes applying anadhesive to one or both of the first substrate and flexible film,abutting the bottom surface of the flexible film and the at least oneflip chip to the first substrate, applying an adhesive to one or both ofthe second substrate and flexible film, abutting the top surface of theflexible film to the second substrate, and exposing the at least onecontact pad through at least one cavity in the second substrate. It isto be appreciated that some of the above steps within block 501 may beinterchanged.

In certain other embodiments which employ conductor patterns in whichthe flip chip and the contact pad are arranged on the same side of theflexible film, e.g. on the top surface of the film, the at least oneflip chip would not be abutted to the first substrate.

In block 503, the carrier core is laminated to produce a laminatedcarrier core.

Particularly, the carrier core is placed or interposed between laminatorplates. This arrangement comprising of laminator plates together withthe interposed carrier core is fed into a lamination machine where thecarrier core is subject to a hot cycle for a time period, e.g. about 30minutes. The hot cycle includes subjecting the carrier core to hightemperature, e.g. at least 80° C., and applying pressure, e.g. at least20 bars or 20×10⁵ pascal (Pa), to the carrier core. Subsequently, thecore is subject to a cold cycle for a period of time, e.g. about 20minutes. The cold cycle includes subjecting the carrier core to lowtemperature, e.g. no more than 30° C., and applying pressure, e.g. atleast 20 bars or 20×10⁵ pascal (Pa), to the carrier core. It is to beappreciated that the time duration, temperature conditions, and pressureconditions may be modified, as known to persons skilled in the art,according to materials and equipment being used.

Due to pressure and temperature conditions during the hot cycle, thefirst substrate is softened and the flip chip(s) are pressed or embeddedinto the softened first substrate. At the same time, due to presence ofa cavity accommodating each contact pad, each contact pad and, in someembodiments, a portion of the flexible film surrounding the contact padwould be urged into and through the space of the cavity. Furtherprojection of the contact pad and any surrounding portion of the filmthrough the cavity are constrained by the laminator plates and,accordingly, in the laminated carrier core, a continuous even plane froman outer surface of the laminated carrier core to the at least onecontact pad is achieved. In other words, no groove or gap will beobserved in the area around contact pad. The result is an aestheticallypleasing and continuously even surface on the side of the laminatedcarrier core where the contact pad is visible and located; and anencapsulation provided by the first or the second substrate to the flipchip.

In block 505, the laminated carrier core is cut or diced into individualsections of ID-1 or other sizes. Reference is made to FIG. 2G which is across-sectional view of an IC-embedded device or smart card device 200cut out from the laminated carrier core 225 d and corresponds to theindividual section 200 referred to in block 411.

FIG. 2G shows a flip chip 250 embedded in a laminated carrier core whichincludes a flexible film 230 having a conductor pattern and interposedbetween a first substrate 220 and a second substrate 240.

The flexible film 230 includes a conductor pattern 210 provided on a topand/or a bottom surface of the film 230. The conductor pattern 210includes at least one flip chip 250 embedded in the first substrate 220,and arranged on a bottom surface of the film 230 and at a position in afirst vertical plane. The conductor pattern 210 further includes ametallic contact pad 260 arranged on a top surface of the film 230abutting the second substrate 240 and at a position in a second verticalplane. The conductor pattern 210 further includes conductor paths 270electrically coupling the contact pad 260 to the flip chip 250. In someembodiments, at least one conductor path traverses a thickness of thefilm 230 to electrically couple the contact pad 260 to the at least oneflip chip 250. The first vertical plane is non-overlapping with thesecond vertical plane. The at least one flip chip module 250 is embeddedinto the first substrate 220 such that the second substrate 240encapsulates the at least one flip chip module. The at least one contactpad 260 is projected through the at least one cavity in the secondsubstrate 240 to form a continuous even plane from an outer surface ofthe laminated carrier core to the at least one contact pad 260.

The first substrate 220 includes a top or inner surface laminated to abottom surface of the film 230 including the at least one flip chip 250.The at least one flip chip module is embedded in the first substrate 220such that the entire body of the second substrate 240 provides anencapsulation to the flip chip module. This encapsulation provides anarea and volume which are greater than flip-chip embedded device andprotect the flip chip from breakage.

The second substrate 240 has a cavity through which the contact pad 260and, in certain embodiments, a portion of the flexible film 230surrounding the contact pad 260, are projected for implementingcontact-type transactions. The second substrate 240 includes a bottom orinner surface laminated to a top surface of the film 230 and a top orouter surface which forms a continuous even plane from an outer surfaceof the laminated carrier core to the at least one contact pad 260. Aregion between the contact pad 260 and the surrounding outer surface ofthe laminated core or second substrate 240 is devoid of groove or gapwhich is otherwise present in existing smart cards fabricated byaforementioned existing methods.

In one embodiment, a thickness of the first substrate 220 is greaterthan a thickness of the second substrate 240. In another embodiment, athickness of the first substrate 220 is substantially the same as athickness of the second substrate 240.

In one embodiment, the laminated carrier core is dimensioned accordingto ID-1 size according to ISO 7810.

In one embodiment, the contact pad 260 is dimensioned according to ISO7816.

In one embodiment, an embossing area, which is designated on thelaminated carrier core according to ISO 7811, particularly ISO 7811-3,is arranged at a position in a third vertical plane, wherein the thirdvertical plane is non-overlapping with the first and the second verticalplane. The embossing area is configured to be embossed with information,e.g. identification number, name and address. Other types of informationmay also be embossed.

Reference is made to FIG. 3G which is a cross-sectional view of anIC-embedded device or smart card device 300 having dual interface i.e.contact and contactless interfaces. The smart card device 300 of FIG. 3Gis similar to FIG. 2G except that the film 230 further includes at leastone antenna coil 280 provided on the top or bottom surface of the film230 and is electrically coupled to the at least one flip chip 250. Theat least one antenna coil 280 is provided at a position in a fourthvertical plane, wherein the fourth vertical plane is non-overlappingwith the first and the second vertical plane.

FIG. 6 is a cross-sectional view of an IC-embedded device or smart carddevice 600 in which the flip chip 250 and contact pad 260 are arrangedon the same side, e.g. top surface, of the flexible film 230.Accordingly, in this embodiment, the at least one flip chip 250 isembedded into and encapsulated by the second substrate 240. Otherdetails of the smart card device 600 are similar to FIG. 2G andtherefore will not be reproduced here.

Embodiments of the invention provide several advantages including butnot limited to the following:

-   -   In existing methods described above, an antenna coil which is        unconnected to any integrated chip module is interposed between        two substrates with equal thickness before milling is performed        to expose portions of the antenna coil. Subsequently, one of        various methods is used to electrically connect the exposed        portions of the antenna coil to the integrated circuit module.

In contrast, with the invention, a single layer (e.g. a film orsubstrate which is preferably flexible and non-metallic) having aconductor pattern comprising at least one flip chip, conductor paths andat least one antenna coil is used. The use of this single sheet inlaywith conductor patterns eliminates the steps for milling the laminatedsubstrate to expose portions of the antenna coil and connecting theexposed portions of the antenna coil to the flip chip. The use of thissingle sheet inlay with conductor patterns also improves the reliabilityof the connection to the antenna coil, as the contact pad and conductorpaths including conductor path connecting the flip chip to antenna coilare laminated onto the film within a same process.

-   -   In the existing methods described above, the flip chip is        located directly on underside of the contact pad (see FIG. 1B)        and therefore the flip chip is prone to damage due to repeated        use from interfacing the contact pad with a contact-type reader.

In contrast, with the invention, the offset arrangement or verticaldis-alignment of the flip chip relative to contact pad reduces the riskof damage to the chip even with repeated use from interfacing thecontact pad with a contact-type reader.

In various embodiments of the invention for fabricating smart carddevices of ID-1 size, the IC module may be positioned on anywhere withinthe ID-1 dimensions other than in the vertical planes for positioningthe contact pad, embossing information, and positioning the antenna coil(for dual interface cards). Accordingly, the lifespan and reliability ofthe IC-embedded device or smart card device of the invention would beimproved.

-   -   In the existing methods described above, the IC chip 150 is        provided with an encapsulation 152 having an area and volume        which are a fraction of the smart card device 100 or contact pad        160 of the smart card module 110.

In contrast, with the invention, the flip chip 250 is embedded in thefirst substrate 220 or second substrate 240 and thus is provided with anencapsulation (i.e. first substrate) having an area and volumesignificantly greater than the contact pad 260 and flip chip 250.Consequently, if a force of same magnitude is separately applied to anexisting smart card device 100 of FIG. 1B and a smart card device 200,300, 600 of FIGS. 2G, 3G and 6 according to the invention, the existingsmart card device (FIG. 1B) would be subject to greater pressure perunit area due to smaller encapsulation area and is therefore more likelyto break, whereas the smart card device of the invention (FIGS. 2G, 3Gand 6) would be subject to lesser pressure per unit area due to largerencapsulation area and is therefore less likely to break. Accordingly,the larger encapsulation area and volume of the smart card device of theinvention (FIGS. 2G, 3G and 6) provide greater protection to the flipchip and therefore improves the lifespan and reliability of the smartdevice 200, 300, 600.

-   -   In existing smart card device 100 of FIG. 1B, there are gaps 190        between the contact pad 160 and the surrounding substrate 140 of        the carrier core. These gaps often, while narrow, often        accumulate dirt and grime.

In contrast, with the invention, the contact pad 260 and, in certainembodiments, a portion of the surrounding film is projected through acavity during lamination and to provide a continuous even plane from anouter surface of the carrier core to the at least one contact pad withno groove or gap between the contact pad and carrier core.

It is to be understood that the embodiments and features described aboveshould be considered exemplary and not restrictive. Many otherembodiments will be apparent to those skilled in the art fromconsideration of the specification and practice of the invention.Furthermore, certain terminology has been used for the purposes ofdescriptive clarity, and not to limit the disclosed embodiments of theinvention.

The invention claimed is:
 1. A smart card device comprising: a laminatedcarrier core comprising: a first substrate; a second substrate; and aflexible film having a conductor pattern and interposed between thefirst and the second substrate, characterised in that the conductorpattern includes: at least one flip chip embedded into the first or thesecond substrate, a contact pad arranged offset relative to the at leastone flip chip, at least one conductor path electrically coupling thecontact pad to the at least one flip chip, wherein the at least oneconductor path and the contact pad are formed on the flexible film andwherein the contact pad is projected through a cavity in the secondsubstrate to form a continuous even plane from an outer surface of thelaminated carrier core to the contact pad such that a region between thecontact pad and the outer surface of the laminated carrier core isdevoid of gap.
 2. The smart card device of claim 1, wherein thelaminated carrier core is dimensioned as 85.60 mm×53.98 mm.
 3. The smartcard device of claim 2, wherein the contact pad is dimensioned toinclude at least a first contact location, a second contact location, athird contact location, a fifth contact location, a sixth contactlocation, a seventh location wherein the first contact location iswithin 19.23 mm to 20.93 mm from an upper edge of the laminated carriercore and within 10.25 mm and 12.25 mm from a left edge of the laminatedcarrier core, which is adjacent to the upper edge, the second contactlocation is within 21.77 mm to 23.47 mm from the upper edge and within10.25 mm to 12.25 mm from the left edge, the third contact location iswithin 24.31 mm to 26.01 mm from the upper edge and within 10.25 mm to12.25 mm from the left edge, the fifth contact location is within 19.23mm to 20.93 mm from the upper edge and within 17.87 mm to 19.87 mm fromthe left edge, the sixth contact location is within 21.77 mm to 23.47 mmfrom the upper edge and within 17.87 mm to 19.87 mm from the left edge,the seventh contact location is within 24.31 mm to 26.01 mm from theupper edge and within 17.87 mm to 19.87 mm from the left edge, andwherein the contact pad is dimensioned to optionally include a fourthcontact location within 26.85 mm to 28.55 mm from the upper edge andwithin 10.25 mm to 12.25 mm from the left edge, an eighth contactlocation within 26.85 mm to 28.55 mm from the upper edge and within17.87 mm to 19.87 mm from the left edge.
 4. The smart card device ofclaim 3, wherein the outer surface of the laminated core includes anembossing area which is designated on the laminated carrier core and hasa width of 85.47 to 85.90 mm and a height of 24.03 mm.
 5. The smart carddevice of claim 4, wherein the embossing area is configured to beembossed with information being at least one selected from the groupconsisting of identification number, name and address.
 6. The smart carddevice of claim 5, wherein the conductor pattern further includes atleast one antenna coil electrically coupled to the at least one flipchip, wherein the at least one antenna coil is formed on the flexiblefilm.
 7. The smart card device of claim 1, wherein the at least one flipchip and the contact pad are arranged on opposite sides of the flexiblefilm.
 8. The smart card device of claim 7, wherein the conductor patternfurther includes at least one antenna coil electrically coupled to theat least one flip chip, wherein the at least one antenna coil is formedon the flexible film.
 9. The smart card device of claim 1, wherein theat least one flip chip and the contact pad are arranged on same side ofthe flexible film.
 10. The smart card device of claim 9, wherein theconductor pattern further includes at least one antenna coilelectrically coupled to the at least one flip chip, wherein the at leastone antenna coil is formed on the flexible film.
 11. The smart carddevice of claim 1, wherein the conductor pattern further includes atleast one antenna coil electrically coupled to the at least one flipchip, wherein the at least one antenna coil is formed on the flexiblefilm.
 12. The smart card device of claim 11, wherein the first or thesecond substrate provides an encapsulation to the at least one flipchip, the encapsulation having an area and a volume which are greaterthan the contact pad.
 13. The smart card device of claim 1, wherein thefirst or the second substrate provides an encapsulation to the at leastone flip chip, the encapsulation having an area and a volume which aregreater than the contact pad.
 14. The smart card device of claim 2,wherein the conductor pattern further includes at least one antenna coilelectrically coupled to the at least one flip chip, wherein the at leastone antenna coil is formed on the flexible film.
 15. The smart carddevice of claim 3, wherein the conductor pattern further includes atleast one antenna coil electrically coupled to the at least one flipchip, wherein the at least one antenna coil is formed on the flexiblefilm.
 16. The smart card device of claim 4, wherein the conductorpattern further includes at least one antenna coil electrically coupledto the at least one flip chip, wherein the at least one antenna coil isformed on the flexible film.
 17. The smart card device of claim 2,wherein the first or the second substrate provides an encapsulation tothe at least one flip chip, the encapsulation having an area and avolume which are greater than the contact pad.
 18. The smart card deviceof claim 3, wherein the first or the second substrate provides anencapsulation to the at least one flip chip, the encapsulation having anarea and a volume which are greater than the contact pad.
 19. The smartcard device of claim 4, wherein the first or the second substrateprovides an encapsulation to the at least one flip chip, theencapsulation having an area and a volume which are greater than thecontact pad.
 20. The smart card device of claim 5, wherein the first orthe second substrate provides an encapsulation to the at least one flipchip, the encapsulation having an area and a volume which are greaterthan the contact pad.
 21. The smart card device of claim 7, wherein thefirst or the second substrate provides an encapsulation to the at leastone flip chip, the encapsulation having an area and a volume which aregreater than the contact pad.
 22. The smart card device of claim 9,wherein the first or the second substrate provides an encapsulation tothe at least one flip chip, the encapsulation having an area and avolume which are greater than the contact pad.